#include"SList.h"
void SLTPrint(SLTNode* phead)
{
	SLTNode* pcur = phead;
	while (pcur)
	{
		printf("%d->", pcur->data);
		pcur = pcur->next;
	}
	printf("NULL\n");
}
SLTNode* SLTBuyNode(SLTDataType x)
{
	SLTNode* newnode = (SLTNode*)malloc(sizeof(SLTNode));
	if (newnode == NULL)
	{
		perror("malloc fail !");
		exit(1);
	}
	newnode->data = x;
	newnode->next = NULL;
	return newnode;
}
void SLTPushBack(SLTNode** pphead, SLTDataType x)
{
	assert(pphead);
	SLTNode*newnode= SLTBuyNode(x);
	if (*pphead == NULL)
	{
		*pphead = newnode;
	}
	else
	{
		SLTNode* ptail=*pphead;
		while (ptail->next )
		{
			ptail = ptail->next;
		}
		ptail->next = newnode;
	}
}
void SLTPushFront(SLTNode** pphead, SLTDataType x)
{
	assert(pphead&&*pphead);

	SLTNode* newnode = SLTBuyNode(x);
	newnode->next = *pphead;
	*pphead = newnode;
}
void SLTPopBack(SLTNode** pphead)
{
	assert(*pphead && pphead);
	SLTNode* prve = *pphead;
	SLTNode* ptail= *pphead;
	if ((*pphead)->next==NULL)
	{
		free(*pphead);
		*pphead = NULL;
	}
	else
	{
		while (ptail->next)
		{
			 prve = ptail;
			 ptail = ptail->next;
		}
		 free(ptail);
		 ptail = NULL;
		 prve->next = NULL;
	}
}
void SLTPopFront(SLTNode** pphead)
{
	assert(*pphead && pphead);
	SLTNode* next = (*pphead)->next;
	free(*pphead);
	*pphead = next;
}
SLTNode* SLTFind(SLTNode* phead, SLTDataType x)
{
	SLTNode* pcur = phead;
	while (pcur)
	{
		if (pcur->data == x)
		{
			return pcur;
		}
		pcur = pcur->next;
	}
	return NULL;
}
void SLTInsert(SLTNode** pphead, SLTNode* pos, SLTDataType x)
{
	assert(*pphead && pphead);
	SLTNode* newnode=SLTBuyNode( x);
	SLTNode* prev = *pphead;
	if (*pphead == pos)
	{
		SLTPushBack(pphead, x);
	}
	while (prev->next != pos)
	{
		prev = prev->next;
	}
	newnode->next = pos;
	prev->next = newnode;
}